Here are a few that might work for you. I think all of them are currently on Netflix:

Battlestar Galactica (can be dry, but once you get past the first 10 episodes, it gets better. Plus there's a LOT of hours available to keep you on the bike.)

Sherlock (The new BBC series. Not too many episodes yet, but tons of fun.)

Dr. Who (Again, lots to watch and not too serious most of the time. Might be just the thing to watch during physical activity.)

How about a re-watch of X-Files or any of the Star Trek series? Some older stuff here, but possibly worth a dip into pre-2000 television.

As far as comedies, I'm a fan of Arrested Development and Archer, but I totally realize taste varies a lot from person to person.

I also like the videos available on the PBS website for a change of pace. Hard to beat a good NOVA, Nature, etc.

Stuff I haven't seen, but my friends like a lot:
Downton Abbey
True Blood (if you have access to HBO)
Mad Men
Lost
Eureka and Warehouse 13 -- These are (sort of) related TV shows from SciFi Channel. I've seen a handful of episodes of each and they can be kind of lame-o, but also fun and not too serious, so good for being on the bike. Also BF likes 'em. Who knew?

Rewatching the X-Files is always a win and Warehouse 13 is pretty amazing. You might like Once Upon a Time. I haven't enjoyed it much, but it is along your fantasy line. Under the Dome has been fairly interesting, but nothing like the book, so don't keep high expectations.

I ride an exercise bike almost daily, while watching/listening to TV (using head phones). I too really liked "The Wire," feeling it is one of the best crime drama series ever. I have only seen two of the BBC updated "Sherlock Holmes," but really enjoyed them. A new crime drama that hooked me early on is "Low Winter Sun." It reminds me in some ways of "The Wire" and shows like "Homicide: Life on the Streets."

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